fastening & assembly solutions and technology - Approved Business

FAST OCTOBER 2011
TRANSPORTATION
The cutting edge
of vehicle assembly
Self-pierce riveting is an innovative, cost effective and environmentally friendly joining process that
has been adopted across a wide range of industries around the world. Automotive manufacturers
have found some specific benefits in the technology
Self-pierce riveting is used to assemble doors, bonnet, bumpers and scuttle on the Bentley Mulsanne
One of the most significant areas of
growth for the self-pierce riveting
process is in the automotive sector where
the constant battle for increased fuel efficiency
has resulted in the use of ever
more exotic lightweight materials in the
body structures and sub-assemblies.
Today you’ll find self-pierce riveting
being used to join car bodies, truck cabs,
hoods, trunks, doors, and a wide selection
Henrob tools in action on the Fisker Automotive
production line
44
of smaller assemblies in a variety of
materials, either with or without adhesive
bonding.
Self-pierce joining is appealing for
today’s modern automotive assembly
plants because is simple, cost effective
and quick as it does not require additional
operations before assembly takes
place. The process basically involves
joining two or more pieces of material
using a specially designed rivet.
However, unlike conventional riveting
which requires a hole, the self-pierce riveting
process works without the need for
pre-drilling or punching holes.
This means that the self-pierce process
is much easier to integrate into high volume
production lines than conventional
riveting and joining specialist Henrob has
developed a range of riveting tools specially
designed and equipped to work in
fully automated environments.
Today’s cutting edge vehicles use a
variety of lightweight materials including
aluminium alloys, high strength steels
and composites. These materials can’t be
joined efficiently and reliably using conventional
fastening techniques but the
self-pierce riveting process offers a
viable joining method for many of these
exotic materials.
Joint integrity
The demands made on joining processes
for automotive structures are extreme.
From having to withstand high life cycle
fatigue to the ability to remain intact during
high speed crashes, the joints in a
vehicle body have to meet many challenging
strength and integrity requirements.
Self-pierce riveting has proved to
be one of the most suitable joining techniques
to meet these strenuous requirements
in modern vehicle structures.
When implemented correctly, the
joints exhibit high strength coupled with
exceptional fatigue life and energy
absorption characteristics, while a highly
stable and repeatable rivet insertion process,
incorporating real time monitoring,
ensures consistent joint quality and properties.
Volvo Truck in Sweden benefitted
from the advantages of self-pierce riveting
when a weight-saving change of
material in their truck cab from standard
Fisker Karma electric powered vehicle is
assembled using self-piercing technology